Hi All, I have configured Cluster in my location below are the details of structure.

Q drive 40 GB (Quorum) S Drive 4 TB (Storage) M Drive 20 GB (MSDTC)

I tested with Node1 & Node2 (Win Server 2008) both are working fine. Than i installed SQL Cluster on NODE1 and add Node2 in cluster (SQL SERVER 2008) i tested its working very nicely.

ISSUE :- SAN server has been restarted & In my active Node1 showing S & Q drive it not showing M drive. I check with SCSi also not an issue than when i chuck FAIL-OVER CLUSTER ADMINISTRATOR got some errors.

1. Node "1" faild to form a cluster. This was because the witness was not accessible. Please ensure that the witness resource is online and available. Event Id :- 1573

I've noticed sometimes that on new cluster setups the servers will lose the drive letter or even use a different one when you failover, especially with iSCSI connections. check disk manager and see if you can find it there as an unlabeled disk. Might have to re-assign the drive letter to it again on both nodes. 20GB for MSDTC seems like an awefully large volume.